Process for making tobacco sheet material



PROCESS FOR MAKING TOBACCO SHEET MATERIAL Filed Sept. 10, 1946 w SLURRY FIG. I

INVVENTOR YMARTIN H. GURLEY, JR.

4 ATTORNEY Patented Oct. 27, 1953 PROCESS FOR MAKDVG TOBACCO SHEET MATERIAL Martin H. Gurley, Jr., Needham, Mass., assignor, by mesne assignments, to American Machine and Foundry Company, New York, N. Y., a corporation of New Jersey Application September 10, 1946, Serial No. 695,940

4 Claims. (01. 131-440) is relatively dense as compared with natural tobacco leaf or leaf portions and, therefor, does not have as much filling power as might be desired for best use of this material in smoking articles such as cigarettes, cigars, cheroots, and the like.

The present invention, therefore, aims at solving the problem of increasing the filling power of reconstituted tobacco sheet or film material. Filling power may be defined as the volume that a given Weight of reconstituted tobacco sheet material or film occupies under a definite pressure. In other words, if such material is shredded and formed into cigarettes, for example, it is the force exerted by a given weight of shredded reconstituted tobacco sheet or film in a given volume. As an example, therefore, an increase in filling power may be termed the capacity of a smaller weight of reconstituted tobacco sheet or film to occupy the same volume and exert the same expansive force as would a larger weight of untreated reconstituted tobacco sheet or film material.

I have discovered that the filling power of reconstituted tobacco sheet material or film can be increased appreciably in such a way that the apparent density of this material may run as much as seventy-five percent less than equal quantities of untreated material. One manner of obtaining the desired increase in filling power is by subjecting the surface thereof to intense heat for a relatively short period of time which causes portions of the sheet to expand rapidly and permanently out of the normal plane of the sheet. When, therefore, the expanded sheet is used in the manufacture of either cigarettes, cigars or like smoking articles, there is an appreoiable increase in its filling power. I have also found that when reconstituted tobacco sheet or film material is treated in this manner, it has This invention relates to reconstituted tobacco sheet or film material, and more particularly to expanded or puffed reconstituted tobacco sheets and/or films, methods for producing the same, and to smoking articles, such as cigarettes, cigars and the like containing desired quantities of such material.

In the tobacco industry, and particularly that part of the industry relating to the manufacture of cigarettes, cigars and like smoking articles, 19 large quantities of tobacco are rejected annually and sold as waste because it is either impossible or impracticable to utilize them in the manu facture of smoking articles. Obviously the loss of these materials is a serious matter from the point of view of the manufacturers and, therefore, it would be highly desirable if such material could be salvaged and used in the manufacture of smoking articles. Materials now disposed of as waste are tobacco stems, dust, scrap, clippings and other portions which are unsatisfactory in connection with the manufacture of highgrade smoking articles.

From time to time attempts have been made to form tobacco sheets or films which would solve the problem of satisfactorily disposing of or utilizing tobacco waste materials. Processes have been developed for forming tobacco paper utilizing well known paper processes and techniques in which tobacco waste, such as for ex- 39 ample stems and scraps, has been reduced to pulp by the use of chemicals and then according to ordinary paper making techniques converted into paper. These techniques are unsuitable for use either in connection with the present invention in forming my improved tobacco sheet material, carrying out the processes therefor, and producing novel smoking articles, such as cigarettes or cigars, because of the radical changes to whichthese tobacco materials are 40 subjected, and the loss of valuable constituents and properties of natural tobacco.

According to my invention, tobacco sheet or film material may be made along lines similar to those described and disclosed in co-pending Wells and Sowa application, Serial No. 414,221, filed October 9, 1941, for Tobacco Sheet Material, which now has matured as U. S. Patent 2,433,887, in which the final product contains substantially all of the desirable properties and natural eharacteristics of tobacco, especially insofar as aroma, taste and color are concerned, and has the same general appearance of tobacco.

I have foundthat the material produced in accordance with the Wells and Sowa application mates the color of tobacco; it burns better, and more uniformly, and forms a much more satisably in color and composition with that normally obtained from the combustion of tobacco in either cigarettes or cigars.

according to the present invention, expanded tobacco films are shredded into strands or the film is formed directly into filaments substantially the width of the strands of natural shredded tobacco and of any desired length. In the case of cigars, the expanded films are used in large pieces much as long filler tobacco in forming long filler cigars or in smaller pieces for use a better color, that is, it more naturally approxifactoryash, or an ash which compares very favor- In the case of the manufacture of cigarettes,

provide a novel in the formation of short filler cigars. In all cases the shredded films or filaments or film used cigarettes and cigars can be handled either manually or by machine in the same manner as natural shredded tobacco leaves or whole leaves or portions there'oi. The amount ofv shredded expanded reconstituted tobacco or pieces of this material employed in a particular blend in cigarettes or cigars, respectively, will vary according to types of tobacco used in the sheet material and the requirements of a particular manilfacturer.

It is an object of my invention, therefore, to method for producing puffed or expanded reconstituted tobacco sheet or film.

It is a further object of the invention to provid a novel method for forming expanded reconstituted tobacco sheet or film material which more closely simulates natural tobacco than any reconstituted sheet or film heretofore known, and which has greater filling power when used in smoking articles.

It is a further object of my invention to subject reconstituted tobacco sheet or film material to heat for a relatively short period of time and puff or expand portions of the sheet in such a manner that the portions thus expanded remain permanently out of the plane of the face of the unpuffed portions of the material thus treated. In this manner the filling power of the material is greatly enhanced.

My invention also consists in the provision of a novel method for forming reconstituted tobacco sheet or film having greater filling power than any such material heretofore known, and wherein the increased filling power is obtained by subjecting the sheet or film material to intense heat for very. short periods of time in order to expand or puff the sheet without'burning oriclrarring the same or otherwise afiecting the chemical makeup of the material treated.

With these and other objects not specifically mentioned in view, the invention consists in certain combinations andcons-tructions which will be hereinafter fully described, and then set forth in the claims hereunto appended.

In the accompanying drawings, which illustrate a preferred embodiment of' the invention, and form a part or this specification, and wherein the several reference characters designate the same or like elements:

Figure '1 is a diagram-matic'view showing mech anism suitable for carrying out and performing the method; I

Figure 2 is a sheet of reconstituted tobacco sheet material --or film prior to being expanded :or puffed; V

Figure 3 is a view s'howing the same material after "being expanded or pufied;

Figure is a cross-section taken on of Figure-3;

line 4-4 V Figure 5 is a view-0f a cigarette made from filler containing shredded, expanded tobacco sheetmaterial;

Figure 6 is a view of a cigar-having a binder formed of my novel expanded reconstituted tobacco sheet material, and .a composition tobacco filler; and

Figure 7 is an end view of .a cigar in which the filler consists entirely of expanded long or short filler reconstituted tobacco .sheet material.

As mentioned .here'inab'ove, the reconstituted sheet which is made in accordance with this invention, can be used either in the manufacture of cigars, cigarettes :or other like smoking articles.

Therefore, in the following description, no distinction is made between the types of tobacco employed.

In making sheet or film material to be expanded and made available for use in the manufacture of smoking articles, a suitable slurry can be formed from seventy-five per cent stems, which are run through a conventional comminuting machine in order to reduce the stems to extremely fine size after which they are mixed with water, and twenty-five per cent tobacco scrap leaf portions, dust or fines which have also been passed through the comminuting machine and preferably screened to remove any foreign material such as sand mixed therewith. The mixture of comminuted stems and leaves is then placed. in .a vhall of known design, and ball milled for a period of time, preferably sufficient to completely hydrate or gelatim'ze the particles of tobacco being ball milled. Th size of the ball mill and balls, and speed of rotation, control the amount of time necessary to reach the desired state of hydration or gelatinization of the tobacco particles. For instance, it has been found that in a four gallon jar ball mill using threefourths inch nominal size fiint pebbles, the ball milling time may approximate from six to sixteen hours at fifty R. P. M. whereas in a five quart ball mill using the :same size pebbles at sixty R. P. M., the minimum time may run as high as thirteen hours.

Upon completion of the slurry, it is removed from the ball mill, and placed in afilm forming device andformed into a continuous sheet or web. 'Excessmoisture is removed therefrom. The sheet or web material is then ready forexpandi-ng or puffing.

Mechanism suitable for forming'tfilms is shown diagrammatically inFigure 1 In "this mechanism there is provided. a conventional type of film forming unit, designated generally 3, which delivers the sheetmaterial in the formo'f anendless web 4 onto a traveling conveyor 6 running on pu1leys8, It mounted on driving and driven shaft 12, M, respectively. Conveyor :6 preferably isimperforate and is made in the form of an endless band. from material, such as stainless steel or other non-rusting and non-staining ma-- terial. In this way there is no danger of staining or :dfscoloring the sheet or web being formed thereon.

Furthermore, the use of an 'imperforate surface substantially prevents the loss of valuable insoluble constituents of tobacco. It will be seen, therefore, that at allstages in the process of making the reconstituted tobacco sheet care is taken not to lose from the aqueous colloidal dispersion or from the cast sheet films, any of the natural soluble ingredients or constituents of tobacco and that these soluble constituents are reincorporated in the finished sheet 'in substantially the proportions in which they occur in the component tobaccosrafter evaporation of the excess .moisture present .in the aqueous hydrated tobacco dispersion- Following the formation of the sheet. .or web, it is moved through a moisture removing zone and excess moisture is removed therefrom. .In

7 Figure 1 there is shown a hood, designated generally i=6, through which hot air can be delivered against the surface of the web or sheet material to remove the desired amount of moisture therefrom. This may be all or only apart depending upon the condition of the sheet or web desired when it is subjected to expanding ,or-pulfing.

Shaft l2 can be driven continuously at a rate of speed required to remove either all or only a part of the moisture contained in the web. As noted above, it depends upon how much moisture is desired in the web or sheet when it is expanded or puited. It is believed that the expanding or pulling obtained is due in a large part to the vaporization of moisture in the web or sheet and the concomitant formation of a large number of bubbles or pockets e per area in the material treated.

Obviously conveyor 6 can be driven stepwise if desired. The partially dried web or sheet material is delivered by conveyor 6 onto con veyor 15 which in the embodiment selected for purposes of illustration is also an endless band consisting preferably of stainless steel or other heat resistant material. Conveyor it runs upon pulleys l1, l9 mounted on shafts 26, 23. Shaft 28 is driven in timed relation with driving shaft I2 so that the movements of the conveyors 6 and 15 are at the same rate of speed. It is preferred that the movement of conveyors 5 and i5 be continuous because it is believed that it results in a more efficient handling of the web or sheet material being treated. In this manner the web material 3 advancing to the heating zone is gradually heated and when it reaches the zone of greatest heat, it is rapidly expanded or puffed with substantial elimination of danger from scorching or charring.

The speed of Conveyor I5 is governed in part by the thickness and moisture content of web 4. If a web is, say one thousandth of an inch in thickness and contains say five percent moisture, it is necessary to run conveyor 15 faster than when the web being treated is, say four thoussandths of an inch thick and contains the same amount of moisture. Speed of conveyors 5 and I5 is thereby adjusted in accordance with web thickness and moisture content. If conveyor i5 is driven at a faster rate of speed than conveyor 6, provisions can be made in any known manner for controlling movement of web 4 from one conveyor to the other. It is also necessary to take into consideration the temperature and proximity of heat source to the web.

Web 4 which preferably contains between 10-15 percent moisture is passed beneath an expanding unit which may be of any desirable type. illustrated embodiment, reconstituted tobacco sheet web material is expanded by a gas flame impinging device which consists of a transverse rod or tube ill provided with a plurality of jets 2%. The cavities are shown in Fig. 4. An adjustment, somewhat similar to that employed in connection with a Bunsen burner may be used in order to control the intensity of the flame. As shown, an air valve 2| is adiustably mounted on intake pipe 25 of burner tube 18. The size of flame and height or position relative to the web to be expanded is such that the web can be puffed or expanded without burning or charring as it travels therebeneath at a speed sufiicient to allow the flame to impinge against the surface of the web or sheet and pop or blister the surface of the web moving therebeneath. As illustrated in Figure 1, jets 20 are approximately one inch above the surface of web 4 being treated. Gas is conducted from supply pipe 2 t0 the jets through valve 24.

The operation of the flame, with respect to the material passing therebeneath, may be described as a sudden vaporization of the moisture contained in the web, such that moisture in the web In the becomes steam, thereby puffing the Web. The net result is that each pufied portion of the web oonstitutes a planar splitting of each puffed. portion of the web in such a manner that the walls of the puffed portion are approximately one-half the thickness of the original untreated web. For best results it is desirable that the web to be expanded or puffed contain some moisture. I have found that satisfactory results can be ob tained when the material being treated contains from two to sixty-five percent moisture. 1 have also found that some measure of expansion can be obtained when reconstituted tobacco sheet material contains less than five percent. In this case very small pockets are formed in the material, and it is believed that they result from gas generated within the sheet material due to heat decomposition thereof. The temperature of the sheet or web may range between 250 F. and 450 F. and depending upon the thickness of web or sheet and moisture content the time may range from one-tenth to five seconds. I have found that the most satisfactory results obtained when the temperature of the sheet or web ranges between 325350 F. It is also desirable, but entirely necessary, that the tobacco materials which form the reconstituted tobacco sheet be substantially completely hydrated. Tests have shown that the more completely hydrated or gelatinized the tobacco material is, the more uniform and complete is the final puffing or expand ing of the reconstituted tobacco sheet or web.

As a result of the puffing or expanding of the reconstituted tobacco sheet, described hereinabove, it is evident that the apparent density of the sheet is reduced. This reduction in apparent density may run as high as seventy-five percent.

Another desirable result obtained by this method is the formation of a reconstituted tobacco sheet in which the cross-sectional area is permanently increased as a result of the puffing operation so that if cigarettes are formed from this material, either wholly or from admixtures with natural shredded tobacco, there is a definite increase in filling power of reconstituted expanded or puffed sheet material. Due also to the increased area and decreased thickness of those portions of the sheet or web which are puffed, the ash formed when this material is burned approximates more closely the ash of natural tobacco and the odor is more nearly that of natural tobacco although a large portion of the tobacco material in the sheet or film consists of stems.

Obviously other means for pufiing or expanding tobacco sheet material can be employed. If these methods of puffing the sheet material are employed, substantially the same results are obtained.

As the puffed or expanded sheet material 5 is moved by conveyor [5 from the heat treating zone, lengths are out therefrom by a cutting mechanism, consisting of a rotary knife 23, and coacting roller 21 operated in timed relationship with the movement of conveyor It. The lengths can then be packed for storage or they may be used in the formation of cigar filler or binders.

, If the expanded tobacco sheet material is to be used as a cigarette tobacco filler, it can be shredded by any known means and added in desirable quantities to form a desired cigarette tobacco blend.

Figure 5 discloses a cigarette designated generally 40, in which the conventional wrapper 42 encloses a filler consisting of shredded cigarette aoaaau tobacco 44 and shredded expanded reconstituted tobacco filler material 46,- orexpanded preformed reconstituted tobacco filaments 46 in. any desired proportion. It is evident. that the'tobaoco' film or filaments can be made from various types: and combinations of tobacco. For instance, the tobacco sheet material can be. made from relatively expensive tobacco such as Latakla in which it is highly desirous to use all waste because of. the high price thereof. So also, it may be formed of Burl'ey or one or more scrap or waste cigarette type tobaccos and incorporated in. accordance with a particular cigarette manufacturers formula as if it were natural cigarette tobacco leaves. Any desired formula can thus be maintained in accordance with the demands of. a manufacturers particular brand using one or more types of natural shredded tobacco leaves and admixed desired quantities. of shredded expanded tobacco, film material or filaments, either as a blending or flavoring medium or both. or for purposes of bulking.

Figure 6 shows a representation of a cigar B, which may be a long or short filler cigar depending upon the kind of filler used. Cigar 58 has. a wrapper 52, a binder 54 formed from expanded tobacco sheet or film material, and a composite filler consisting of long or short filler tobacco 56, and a desired quantity of pieces of expanded tobacco sheet material or filrn 58 of desired size employed for blending and/ or bulking or natural tobacco filler 5t alone. The amount of expanded tobacco used depends upon the types of tobacco employed in making the reconstituted tobacco sheet, and the requirements of a particular blend. If desired, instead of a binder .formed of tobacco film material, such as 58, a conventional type of tobacco leaf binder may be used. Figure 7' shows a cigar in which the filler consists entirely of expanded long or short filler reconstituted tobacco.

sheet material 65, and a natural leaf binder 62 The invention above described may be varied in construction within the scope of the claims, for the particular device, selected to illustrate the invention, is butone of many possible concrete embodiments of the same. It is not, therefore, to be restricted to the precise details of the structure shown and described.

What I claim is:

l. The method of expanding tobacco reconstituted sheet material comprising placing such material to be treated upon a flame resistant support, and moving said support with said reconstituted tobacco sheet material positioned thereon relative to a source of intense heat to 8; raise the temperature of: said material to between 250"'-450 F. to. vaporize moisture contained within said sheet and puff limited portions thereof.

2. The method of pufiingv reconstituted tobacco sheet material. which. consists in forming, a web containing hydrated tobacco particles on 'a traveling; support, removing, excess moisture from said; web, passing, said web through a heating zone, and subjecting, successive. lengths of said web to heat ranging between 325-350 F. toconvert residual. moisture within said web to steam, and thereby puff said web.

3. The process of. treating substantially dry continuous reconstituted tobacco sheet material, said material containing approximately ten to fifteen percent moisture, which comprises the step of passing said sheet through a zone of: intense heat ranging in. temperature from 250-450 Fl; whereby the moisture in said. sheet is converted to steam to thereby expand and puff said sheet.

4. The method of puffing substantially noncellular reconstituted tobacco sheet material wherein the constituents" thereof are substantially entirely tobacco having therein an appreciable volume of moisture, which consists in moving said material in web form through a drying zone to remove substantially all moisture therefrom and then passing said material in the latter condition through a heating zone and simultaneously applying to said reconstituted Webof tobacco material while in said zone intense heat to raise the temperature of said material to a. temperature of between 250 450 F. thereby vaporizing substantially all the remaining moisture therein and simultaneously expanding portions of said sheet.

MARTIN H. GURLEY, J 11.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,121,660 Plotkin Dec. 22, 1914 1,789,435 Hawkins Jan. 20, 1931 2,433,877 Wells et a1. Jan. 6, I948 FOREIGN PATENTS Number Country Date 7 261,520 Great Britain Nov. 25, 1926 570,265 Great Britain June 29, 1945 OTHER REFERENCES Alien Property Custodian application of Joachim Bohmeand Karl Suntheimer, Serial No. 304,214, published May 11, 1943, now abandoned. 

